Methods Of Forming An Array Of Elevationally-Extending Strings Of Memory Cells, Methods Of Forming Polysilicon, Elevationally-Extending Strings Of Memory Cells Individually Comprising A Programmable Charge Storage Transistor, And Electronic Components Comprising Polysilicon

ABSTRACT

A method of forming poly silicon comprises forming a first polysilicon-comprising material over a substrate, with the first polysilicon-comprising material comprising at least one of elemental carbon and elemental nitrogen at a total of 0.1 to 20 atomic percent. A second polysilicon-comprising material is formed over the first polysilicon-comprising material. The second polysilicon-comprising material comprises less, if any, total elemental carbon and elemental nitrogen than the first polysilicon-comprising material. Other aspects and embodiments, including structure independent of method of manufacture, are disclosed.

TECHNICAL FIELD

Embodiments disclosed herein pertain to methods of forming an array ofelevationally-extending strings of memory cells, to methods of formingpolysilicon, to elevationally-extending strings of memory cellsindividually comprising a programmable charge storage transistor, and toelectronic components comprising polysilicon.

BACKGROUND

Memory provides data storage for electronic systems. Flash memory is onetype of memory, and has numerous uses in computers and other devices.For instance, personal computers may have BIOS stored on a flash memorychip. As another example, flash memory is used in solid state drives toreplace spinning hard drives. As yet another example, flash memory isused in wireless electronic devices as it enables manufacturers tosupport new communication protocols as they become standardized, and toprovide the ability to remotely upgrade the devices for improved orenhanced features.

A typical flash memory comprises a memory that includes a large numberof memory cells arranged in row and column fashion. The flash memory maybe erased and reprogrammed in blocks. NAND may be a basic architectureof flash memory. A NAND cell unit comprises at least one selectingdevice coupled in series to a serial combination of memory cells (withthe serial combination commonly being referred to as a NAND string).Example NAND architecture is described in U.S. Pat. No. 7,898,850.

Memory cell strings in flash or other memory may be arranged to extendhorizontally or vertically. Vertical memory cell strings reducehorizontal area of a substrate occupied by the memory cells incomparison to horizontally-extending memory cell strings, albeittypically at the expense of increased vertical thickness.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic sectional view of a substrate fragment inprocess in accordance with an embodiment of the invention.

FIG. 2 is a diagrammatic top plan view of the FIG. 1 substrate at aprocessing step subsequent to that shown by FIG. 1.

FIG. 3 is a view taken through line 3-3 in FIG. 2.

FIG. 4 is a view of the FIG. 3 substrate at a processing step subsequentto that shown by FIG. 3.

FIG. 5 is a view of FIG. 4 substrate at a processing step subsequent tothat shown by FIG. 4.

FIG. 6 is a view of the FIG. 5 substrate at a processing step subsequentto that shown by FIG. 5.

FIG. 6A is an enlargement of a portion of FIG. 6.

FIG. 6B is a diagrammatic sectional view of a substrate fragment inprocess in accordance with an embodiment of the invention, and is at theenlarged scale of FIG. 6A.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Embodiments of the invention include methods of forming polysilicon.Such method embodiments are described with respect to fabrication of anarray of elevationally-extending strings of memory cells havingpolysilicon-comprising channels, although such polysilicon may be formedas part of any electronic component or of any construction that is notan electronic component. Embodiments of the invention also includeelevationally-extending strings of memory cells independent of method ofmanufacture, with the memory cells individually comprising aprogrammable charge storage transistor. In this document,“elevationally-extending” and “extend(ing) elevationally” refer to adirection that is angled away by at least 45° from a primary surfacerelative to which a substrate is processed during fabrication and whichmay be considered to define a generally horizontal direction. Further,“vertical” and “horizontal” as used herein are generally perpendiculardirections relative one another independent of orientation of thesubstrate in three dimensional space. Further and unless otherwiseindicated, “elevational(ly)”, “higher”, “upper”, “lower”, “top”, “atop”,“bottom”, “above, “below”, “under”, “beneath”, “up”, and “down” aregenerally with reference to the vertical direction. Also,“elevationally-extending” and “extend(ing) elevationally” with respectto a field effect transistor are with reference to orientation of thetransistor's channel length along which current flows in operationbetween the source/drain regions. Embodiments of the invention alsoinclude electronic components comprising polysilicon independent ofmethod of manufacture.

Referring to FIG. 1, a substrate fragment or construction 10 may beconsidered as comprising a base substrate 12 that may include any one ormore of conductive/conductor/conducting (i.e., electrically herein),semiconductive, or insulative/insulator/insulating (i.e., electricallyherein) materials. Various materials are shown above base substrate 12.Materials may be aside, elevationally inward, or elevationally outwardof the FIG. 1-depicted materials. For example, other partially or whollyfabricated components of integrated circuitry may be provided somewhereabove, about, or within substrate 12. Control and/or other peripheralcircuitry for operating components within a memory array may also befabricated, and may or may not be wholly or partially within a memoryarray or sub-array. Further, multiple sub-arrays may also be fabricatedand operated independently, in tandem, or otherwise relative oneanother. As used in this document, a “sub-array” may also be consideredas an array. Regardless, any of the materials, regions, and structuresdescribed herein may be homogenous or non-homogenous, and regardless maybe continuous or discontinuous over any material which such overlie.Further, unless otherwise stated, each material may be formed using anysuitable or yet-to-be-developed technique, with atomic layer deposition,chemical vapor deposition, physical vapor deposition, epitaxial growth,diffusion doping, and ion implanting being examples.

Example substrate 12 comprises semiconductor material 17, for examplemonocrystalline silicon, having a conductively doped source material 19formed there-over or therein and which may comprise a portion ofcircuitry for the elevationally-extending strings of memory cells beingfabricated. An insulator 18 (e.g., doped or undoped silicon dioxideand/or silicon nitride) is shown elevationally between semiconductormaterial 17 and material 19. An example source material 19 isconductively doped polysilicon of 500 Angstroms thickness over anunderlying tungsten silicide of 900 Angstroms thickness. An examplethickness for insulator 18 is 2,000 to 5,000 Angstroms. In thisdocument, “thickness” by itself (no preceding directional adjective) isdefined as the mean straight-line distance through a given material orregion perpendicularly from a closest surface of an immediately adjacentmaterial of different composition or of an immediately adjacent region.Additionally, the various materials or regions described herein may beof substantially constant thickness or of variable thicknesses. If ofvariable thickness, thickness refers to average thickness unlessotherwise indicated, and such material or region will have some minimumthickness and some maximum thickness due to the thickness beingvariable. As used herein, “different composition” only requires thoseportions of two stated materials or regions that may be directly againstone another to be chemically and/or physically different, for example ifsuch materials or regions are not homogenous. If the two statedmaterials or regions are not directly against one another, “differentcomposition” only requires that those portions of the two statedmaterials or regions that are closest to one another be chemicallyand/or physically different if such materials or regions are nothomogenous. In this document, a material, region, or structure is“directly against” another when there is at least some physical touchingcontact of the stated materials, regions, or structures relative oneanother. In contrast, “over”, “on”, “adjacent”, “along”, and “against”not preceded by “directly” encompass “directly against” as well asconstruction where intervening material(s), region(s), or structure(s)result(s) in no physical touching contact of the stated materials,regions, or structures relative one another.

A material stack 24 has been formed over substrate 12 and comprisesvertically-alternating tiers of control gate material 26 and insulativematerial 28 (e.g., doped or undoped silicon dioxide and/or siliconnitride). Control gate material 26 is conductive, with an example beingconductively doped polysilicon. Example thicknesses for each ofmaterials 26 and 28 are 200 to 400 Angstroms, and such need not be ofthe same respective thicknesses or of the same thickness relative oneanother when materials 26 and 28 individually are of constant thickness.Material stack 24 is shown as having twelve vertically-alternatingtiers, although fewer or likely many more (e.g., dozens, hundreds, etc.)may be formed. The top layer of material 28 of material stack 24 may bemade thicker or thinner than shown or an alternate material providedthere-over (not shown) where desired as an etch-stop or polish-stop forbetter assuring a planar horizontal substrate (if desired).

Referring to FIGS. 2 and 3, elevationally-extending channel openings 23have been formed into vertically-alternating tiers of materials 26, 28.Only two such channel openings are formed, although likely hundreds,thousands, etc. would be formed for formation of hundreds, thousands,etc. of elevationally-extending strings of memory cells. Exampletechniques for forming channel openings 23 include dry anisotropicplasma etching using lithography with or without pitch multiplication(e.g., using photoresist and/or other imageable and/or non-imageablematerials, including hard masking materials). Channel openings 23 may becircular, ellipsoidal, rectangular, or of other shape in horizontalcross-section, with circular being shown. In one embodiment and asshown, channel openings 23 extend completely through material 24 andpartially into material 19. Channel openings 23 individually may have anexample maximum horizontal open dimension of 850 to 1,250 Angstroms attheir elevationally-outermost portions and which taper (not shown) to ahorizontal open dimension of 5 percent to 10 percent less at theirelevationally-innermost portions where meeting with source material 19.In one embodiment, channel openings 23 are formed to be vertical orwithin 10° vertical.

Polysilicon-comprising channel material is formed in the channelopenings in a novel manner or manners in method embodiments as describedbelow. Further, control gate material, control gate blocking insulator,programmable charge storage material, and tunnel insulator areultimately provided operably proximate the polysilicon-comprisingchannel material either before or after forming such channel material.

Referring to FIG. 4 and in one embodiment, control gate material 26 hasbeen subjected an anisotropic wet etch to laterally recess it relativeto the original sidewalls of channel opening 23. Such an etch may beconducted selectively relative to materials 28 and 19. In this document,a selective etch or removal is where one material is removed relative toanother stated material at a rate of at least 2:1.

Referring to FIG. 5, several acts of processing have occurred relativeto FIG. 4. Specifically, control gate blocking insulator 40 (e.g., oneor more of silicon nitride, silicon dioxide, hafnium oxide, zirconiumoxide, etc.), programmable charge storage material 42 (e.g., materialsuitable for utilization in floating gates or charge-trappingstructures, such as, for example, one or more of silicon, siliconnitride, nanodots, and tunnel insulator 44 (e.g., one or more of silicondioxide and silicon nitride) have been sequentially formed in channelopenings 23. Such are shown as having been subjected to an etch (e.g.,wet isotropic etch by exposure to one of HF and H₃PO₄ or by a dryanisotropic etch) to remove such from being substantially overhorizontal surfaces before deposition of the next subsequent layer.Alternately and by way of example only, such may be subjected to suchetching after deposition of two or more such layers, where for example agoal is for a subsequently deposited channel material to electricallycouple with source material 19.

Referring to FIG. 6, polysilicon-comprising channel material 50 and adielectric material 52 (e.g., silicon nitride and/or doped or undopedsilicon dioxide) have been formed to fill remaining volume of channelopenings 23, followed by planarizing materials 50 and 52 back at leastto an elevationally-outermost surface of the elevationally-outermostmaterial 28. Accordingly, polysilicon-comprising channel material 50 isshown as comprising a channel pillar in individual channel openings 23in the form of a hollow channel pillar internally filled with dielectricmaterial 52. Alternately, polysilicon-comprising channel material 50 mayextend completely diametrically across channel openings 23 (e.g., nointernal dielectric material 52 and not shown) thereby formingnon-hollow channel pillars. Regardless, channel material 50 comprisesdoped polysilicon-comprising material having channelconductivity-modifying dopant(s) present in a quantity that producesintrinsic semiconductor properties enabling the channel material tooperably function as switchable “on” and “off” channels for theindividual memory cells for control gate voltage above and below,respectively, a suitable threshold voltage (V_(t))depending onprogramming state of the charge storage transistor for the respectiveindividual memory cell. An example such dopant quantity is 5×10¹⁷atoms/cm³ to 5×10¹⁸ atoms/cm³. Polysilicon-comprising channel material50 may be p-type or n-type.

In accordance with method embodiments, polysilicon-comprising channelmaterial 50 is formed in a novel manner, and which is describedinitially with reference to FIG. 6A which is an enlargement of a portionof tunnel insulator 44, polysilicon-comprising channel material 50, anddielectric material 52. Specifically, FIG. 6A shows formation of a firstpolysilicon-comprising material 36 in channel openings 23 and formationof a second polysilicon-comprising material 38 in channel openings 23over first polysilicon-comprising material 36. In one embodiment and asshown, second polysilicon-comprising material 38 is formed directlyagainst first polysilicon-comprising material 36. Regardless, firstpolysilicon-comprising material 36 is formed to comprise at least one ofelemental carbon and elemental nitrogen at a total of 0.1 to 20 atomicpercent, and in one embodiment form 0.5 to 2 atomic percent. In oneembodiment, first polysilicon-comprising material 36 comprises bothelemental carbon and elemental nitrogen. In one embodiment, firstpolysilicon-comprising material 36 comprises only one of elementalcarbon and elemental nitrogen, in one such embodiment comprisingelemental carbon and in another such embodiment comprising elementalnitrogen. Regardless, second polysilicon-comprising material 38 isformed to comprise less, if any, total elemental carbon and elementalnitrogen than first polysilicon-comprising material 36. In oneembodiment, such total in the second polysilicon-comprising material iszero to 0.001 atomic percent.

In one embodiment, first polysilicon-comprising material 36 is formed toa thickness that is 2 to 70 percent of the thickness of secondpolysilicon-comprising material 38, and in one embodiment to a thicknessthat is 2 to 30 percent of the thickness of secondpolysilicon-comprising material 38. FIG. 6A shows an embodiment whereinfirst polysilicon-comprising material 36 has been formed to be thinnerthan second polysilicon-comprising material 38. FIG. 6B shows analternate embodiment construction 10 a wherein firstpolysilicon-comprising material 36 a has been formed to be thicker thansecond polysilicon-comprising material 38 a in a polysilicon-comprisingchannel material 50 a. Like numerals from the above-describedembodiments have been used, with differences being indicated with thesuffix “a”. Any other attribute(s) or aspect(s) as shown and/ordescribed above may be used.

By ways of examples only, polysilicon-comprising materials 36/36 a and38/38 a can be formed by any suitable existing or yet-to-be-developedmanners, such as ALD, CVD, LPCVD, and/or PECVD. In one ideal embodiment,second polysilicon-comprising material 38/38 a is formed in situ in thesame deposition chamber as first polysilicon-comprising material 36/36 aand immediately thereafter. Regardless, example silicon-containingprecursors for materials 36/36 a and 38/38 a are any silane and silicontetrachloride. Example precursors for carbon atoms are any suitablehydrocarbon(s), and example precursors for nitrogen atoms are any one ormore of NH₃, N₂O, NO, and N₂. Example volumetric flow rate for each(when greater than zero) is 0.1 to 1,000 sccm. Example substratetemperature is 250° C. to 1,000° C., example chamber pressure is 1 mTorrto room atmospheric, and example power is 0 to 7,000 Watts. An inert gasmay additionally be provided to the deposition chamber at 0 sccm to 1slm.

In one embodiment, first polysilicon-comprising material 36/36 a andsecond polysilicon-comprising material 38/38 a are formed to have atleast 30 percent 111 crystal orientation (as measured by electronbackscatter diffraction [EBSD]), and in one embodiment at least 50percent 111 crystal orientation as measured by EBSD. Such may not resultupon initial formation of channel material 50/50 a, and may resultthereafter from being exposed to suitable annealing conditions. Forexample, channel material 50/50 a as initially formed may be amorphousor partially crystalline. Example annealing conditions are substratetemperature of 500° C. to 1,000° C., chamber pressure of 1 mTorr to roomatmospheric, an inert or H₂ atmosphere, and time of such annealing from15 nanoseconds to 48 hours.

Polycrystalline silicon (i.e., polysilicon) as-formed uponcrystallization anneal has multiple individual crystal grains forminggrain boundaries between immediately-adjacent grains. Individual grainsinclude a large number of individual crystal unit cells that aretypically of one of varying different Miller indices. Typically withinan individual crystal grain, there is a uniformity of unit cells of thesame Miller index crystal orientation. For example, typical polysiliconupon crystallization anneal overall has about 25 percent grainscontaining 111 orientation, 15 percent grains containing 220orientation, 7 to 10 percent having 311 orientation, with the remaindereach individually being of a different orientation of less than 7percent each, and totaling 50 to 53 of the whole (each as measured byEBSD).

Maximizing of the 111 orientation is desired or ideal as such results inthe greatest conductivity for a given concentration ofconductivity-enhancing dopant in the polysilicon. Such results from the111 crystal lattice inherently aligning perpendicular to theimmediately-adjacent surface over which such material is formed, andwhich is typically orthogonal to current flow through the polysilicon.Additionally for maximizing conductivity in conductively-dopedpolysilicon, larger grains produce higher electrical conductivity thansmaller grains. Fabricating of a polysilicon material as describedherein with at least the stated first and second polysilicon-comprisingmaterials may achieve greater than 50 percent 111 crystal grains asmeasured by EBSD, and can result in a crystal grain size that is 2 to 5times as great in average diameter in comparison to polysilicondeposition and anneal in the absence of providing the stated first andsecond poly silicon-comprising materials.

FIG. 6 shows formation of elevationally-extending strings 80 ofindividual memory cells 88. Construction 10 is shown as comprising asingle memory cell 88 about the channel pillar in each tier of theelevationally-extending strings of memory cells. Alternately, and by wayof example only, any existing or yet-to-be-developed construction may beused wherein two or more memory cells are circumferentially spaced aboutthe channel pillar in a single tier in a given string (not shown).Regardless, example memory cells 88 comprise a programmable chargestorage transistor comprising materials 50, 44, 42, 40, and 26, and inone embodiment as shown extend elevationally.

The above-described processing was by way of example with respect toso-called “gate first” processing in comparison to so-called “gate last”or “replacement gate” processing. Accordingly and in one embodiment, thevertically-alternating tiers are formed to be vertically-alternatinginsulating material and control gate material prior to forming thechannel openings. However, gate last/replacement gate processing may beused whereby a FIG. 1-starting-construction may be with a material 24comprising alternating tiers of different composition insulatingmaterials (i.e., no control gate material 26 yet) with one of suchinsulating materials being replaced with control gate material 26 afterforming the control gate blocking insulator, the programmable chargestorage material, the tunnel insulator, and the channel material inchannel openings 23. Accordingly and in one embodiment, the verticallyalternating tiers are formed to be different composition insulatingmaterials prior to forming the channel openings.

Further as stated above, processing may occur in forming polysiliconregardless of resulting integrated circuitry construction, and may occurwhere the resulting construction does not include integrated circuitry.Such a method of forming polysilicon comprises forming a firstpolysilicon-comprising material over a substrate, with suchpolysilicon-comprising material comprising at least one of elementalcarbon and elemental nitrogen at a total of 0.1 to 20 atomic percent. Asecond polysilicon-comprising material is formed over the firstpolysilicon-comprising material, with the second polysilicon-comprisingmaterial comprising less, if any, total elemental carbon and elementalnitrogen than does the first polysilicon-comprising material. Any otherattribute(s) or aspect(s) as shown and/or described above may be used.

Embodiments of the invention comprise an elevationally-extending string(e.g., 80) of memory cells (e.g, 88) individually comprising aprogrammable charge storage transistor (e.g., encompassed by materials50, 44, 42, 40, and 26 in an individual tier) independent of method ofmanufacture. Such a string comprises vertically-alternating tiers ofinsulative material (e.g., 28) and control gate material (e.g., 26). Achannel pillar (e.g., material 50) extends elevationally throughmultiple of the vertically-alternating tiers. The channel materialcomprises radially outer first polysilicon-comprising material (e.g.,36/36 a) comprising at least one of elemental carbon and elementalnitrogen at a total of 0.1 to 20 atomic percent. The channel materialcomprises a second polysilicon-comprising material (e.g., 38/38 a)radially inward of the first polysilicon-comprising material. The secondpolysilicon-comprising material comprises less, if any, total elementalcarbon and elemental nitrogen than does the first polysilicon-comprisingmaterial. A tunnel insulator (e.g., 44), programmable charge storagematerial (e.g., 42) and control gate blocking insulator (e.g., 40) arebetween the channel pillar and the control gate material of individualof the tiers of the control gate material. Any other attribute(s) oraspect(s) as shown and/or described above may be used.

Embodiments of the invention also encompass any electronic component(e.g., a diode, a transistor, a resistor, a transducer, a switch, afuse, an antifuse, etc.) comprising polysilicon. The polysilicon of suchan electronic component comprises a first polysilicon-comprisingmaterial proximate a second polysilicon-comprising material. The firstpolysilicon-comprising material comprises at least one of elementalcarbon and elemental nitrogen at a total of 0.1 to 20 atomic percent.The second polysilicon-comprising material comprises less, if any, totalelemental carbon and elemental nitrogen that does the firstpolysilicon-comprising material. In one embodiment, the first and secondpolysilicon-comprising materials are directly against one another. Inone embodiment, the component is a field effect transistor, and thefirst and second polysilicon-comprising materials comprise a channelregion of the field effect transistor. In other example embodiments, theelectronic component comprising such polysilicon is any one of a diode,a transistor, a resistor, a transducer, a switch, a fuse, and anantifuse. Any other attribute(s) or aspect(s) as shown and/or describedabove may be used.

CONCLUSION

In some embodiments, a method of forming an array ofelevationally-extending strings of memory cells, where the memory cellsindividually comprise a programmable charge storage transistor,comprises forming vertically-alternating tiers of different compositionmaterials. Elevationally-extending channel openings are formed into thevertically-alternating tiers. Polysilicon-comprising channel material isformed in the channel openings. The forming of thepolysilicon-comprising channel material comprises forming a firstpolysilicon-comprising material in the channel openings, with the firstpolysilicon-comprising material comprising at least one of elementalcarbon and elemental nitrogen at a total of 0.1 to 20 atomic percent. Asecond polysilicon-comprising material is formed in the channel openingsover the first polysilicon-comprising material. The secondpolysilicon-comprising material comprises less, if any, total elementalcarbon and elemental nitrogen than the first polysilicon-comprisingmaterial. Control gate material, control gate blocking insulator,programmable charge storage material, and tunnel insulator are providedoperably proximate the channel material.

In some embodiments, a method of forming polysilicon comprises forming afirst polysilicon-comprising material over a substrate, with the firstpolysilicon-comprising material comprising at least one of elementalcarbon and elemental nitrogen at a total of 0.1 to 20 atomic percent. Asecond polysilicon-comprising material is formed over the firstpolysilicon-comprising material. The second polysilicon-comprisingmaterial comprises less, if any, total elemental carbon and elementalnitrogen than the first polysilicon-comprising material.

In some embodiments, an elevationally-extending string of memory cellsindividually comprising a programmable charge storage transistorcomprises vertically-alternating tiers of insulative material andcontrol gate material. A channel pillar extends devotionally throughmultiple of the vertically-alternating tiers. The channel pillarcomprises radially outer first polysilicon-comprising materialcomprising at least one of elemental carbon and elemental nitrogen at atotal of 0.1 to 20 atomic percent. The channel pillar comprises secondpolysilicon-comprising material radially inward of the firstpolysilicon-comprising material. The second polysilicon-comprisingmaterial comprises less, if any, total elemental carbon and elementalnitrogen than the first polysilicon-comprising material. Tunnelinsulator, programmable charge storage material, and control gateblocking insulator are between the channel pillar and the control gatematerial of individual of the tiers of the control gate material.

In some embodiments, an electronic component comprising polysiliconcomprises a first polysilicon-comprising material proximate a secondpolysilicon-comprising material, with the first polysilicon-comprisingmaterial comprising at least one of elemental carbon and elementalnitrogen at a total of 0.1 to 20 atomic percent. The secondpolysilicon-comprising material comprises less, if any, total elementalcarbon and elemental nitrogen than the first polysilicon-comprisingmaterial.

In compliance with the statute, the subject matter disclosed herein hasbeen described in language more or less specific as to structural andmethodical features. It is to be understood, however, that the claimsare not limited to the specific features shown and described, since themeans herein disclosed comprise example embodiments. The claims are thusto be afforded full scope as literally worded, and to be appropriatelyinterpreted in accordance with the doctrine of equivalents.

1-18. (canceled)
 19. A method of forming polysilicon, comprising:forming a first polysilicon-comprising material over a substrate, thefirst polysilicon-comprising material comprising at least one ofelemental carbon and elemental nitrogen at a total of 0.1 to 20 atomicpercent; and forming a second polysilicon-comprising material over thefirst polysilicon-comprising material, the second polysilicon-comprisingmaterial comprising less, if any, total elemental carbon and elementalnitrogen than the first polysilicon-comprising material.
 20. Anelevationally-extending string of memory cells individually comprising aprogrammable charge storage transistor, comprising:vertically-alternating tiers of insulative material and control gatematerial; a channel pillar extending elevationally through multiple ofthe vertically-alternating tiers; the channel pillar comprising radiallyouter first polysilicon-comprising material comprising at least one ofelemental carbon and elemental nitrogen at a total of 0.1 to 20 atomicpercent; the channel pillar comprising second polysilicon-comprisingmaterial radially inward of the first polysilicon-comprising material,the second polysilicon-comprising material comprising less, if any,total elemental carbon and elemental nitrogen than the firstpolysilicon-comprising material; and tunnel insulator, programmablecharge storage material, and control gate blocking insulator between thechannel pillar and the control gate material of individual of the tiersof the control gate material.
 21. An electronic component comprisingpolysilicon, the polysilicon comprising: a first polysilicon-comprisingmaterial proximate a second polysilicon-comprising material, the firstpolysilicon-comprising material comprising at least one of elementalcarbon and elemental nitrogen at a total of 0.1 to 20 atomic percent,the second polysilicon-comprising material comprising less, if any,total elemental carbon and elemental nitrogen than the firstpolysilicon-comprising material.
 22. The electronic component of claim21 wherein the first and second polysilicon-comprising materials aredirectly against one another.
 23. The electronic component of claim 21wherein the component is a field effect transistor, and the first andsecond polysilicon-comprising materials comprise a channel region of thefield effect transistor.
 24. The electronic component of claim 23wherein the first and second polysilicon-comprising materials aredirectly against one another.